Heterogeneous network in LTE-advanced system

This paper provides a thorough analysis of the frequency resource allocation among multi-layers of the intra-RAT (Radio Access Technology) heterogeneous network. From the aspect of the spectrum utilization efficiency, the co-channel heterogeneous network provides higher system capacity, but its control channel coverage and quality is much worse than the orthogonal frequency allocation between macro cell and local cells. Enhancement of co-channel deployment are analyzed and evaluated such as range expansion and the Frequency Division Duplexing (FDM)/Time Division Duplexing (TDM) orthogonal control channel design. As a further step of evolution, an approach with dynamic spectrum sharing among macro cells and local cells are proposed to utilize the spared macro uplink resource in the downlink/uplink traffic asymmetric scenario for hotspot local DL access with well-designed interference management.